Electrical performance of finlines of various configurations

The characteristics of new microwave integrated circuits called earthed and isolated finlines, namely the cutoff wavelength, the equivalent dielectric constant, attenuation constant, and characteristic impedance based on power-voltage and power-current definitions are calculated. The ridged waveguide characteristics are found direct from the results of the earthed finline setting ?r = 1. For some symmetrical configurations the transcendental equations resulting from the calculations can be solved approximately; the results being represented in a closed form approximate to those arising from numerical calculations to a high degree. Some of the results are confirmed by measurements.